Crate core [] [src]

Unstable (core #27701)

: the libcore library has not yet been scrutinized for stabilization in terms of structure and naming

The Rust Core Library

The Rust Core Library is the dependency-free foundation of The Rust Standard Library. It is the portable glue between the language and its libraries, defining the intrinsic and primitive building blocks of all Rust code. It links to no upstream libraries, no system libraries, and no libc.

The core library is minimal: it isn't even aware of heap allocation, nor does it provide concurrency or I/O. These things require platform integration, and this library is platform-agnostic.

It is not recommended to use the core library. The stable functionality of libcore is reexported from the standard library. The composition of this library is subject to change over time; only the interface exposed through libstd is intended to be stable.

How to use the core library

This library is built on the assumption of a few existing symbols:

Modules

any

This module implements the Any trait, which enables dynamic typing of any 'static type through runtime reflection.

borrow

A module for working with borrowed data.

cell

Shareable mutable containers.

char

Character manipulation.

clone

The Clone trait for types that cannot be 'implicitly copied'

cmp

Functionality for ordering and comparison.

convert

Traits for conversions between types.

default

The Default trait for types which may have meaningful default values.

f32

Operations and constants for 32-bits floats (f32 type)

f64

Operations and constants for 64-bits floats (f64 type)

fmt

Utilities for formatting and printing strings

hash

Generic hashing support.

i16

The 16-bit signed integer type.

i32

The 32-bit signed integer type.

i64

The 64-bit signed integer type.

i8

The 8-bit signed integer type.

isize

The pointer-sized signed integer type.

iter

Composable external iteration

marker

Primitive traits and marker types representing basic 'kinds' of types.

mem

Basic functions for dealing with memory

num

Numeric traits and functions for the built-in numeric types.

ops

Overloadable operators

option

Optional values

prelude

The libcore prelude

ptr

Raw, unsafe pointers, *const T, and *mut T

result

Error handling with the Result type

slice

Slice management and manipulation

str

String manipulation

sync

Synchronization primitives

u16

The 16-bit unsigned integer type.

u32

The 32-bit unsigned integer type.

u64

The 64-bit unsigned integer type.

u8

The 8-bit unsigned integer type.

usize

The pointer-sized unsigned integer type.

array [Unstable]

Implementations of things like Eq for fixed-length arrays up to a certain length. Eventually we should able to generalize to all lengths.

intrinsics [Unstable]

rustc compiler intrinsics.

nonzero [Unstable]

Exposes the NonZero lang item which provides optimization hints.

panicking [Unstable]

Panic support for libcore

raw [Unstable]

Contains struct definitions for the layout of compiler built-in types.

simd [Deprecated]

SIMD vectors.

Macros

__impl_slice_eq1!
__impl_slice_eq2!
assert!

Ensure that a boolean expression is true at runtime.

assert_eq!

Asserts that two expressions are equal to each other.

debug_assert!

Ensure that a boolean expression is true at runtime.

debug_assert_eq!

Asserts that two expressions are equal to each other, testing equality in both directions.

panic!

Entry point of thread panic, for details, see std::macros

try!

Short circuiting evaluation on Err

unimplemented!

A standardized placeholder for marking unfinished code. It panics with the message "not yet implemented" when executed.

unreachable!

A utility macro for indicating unreachable code.

write!

Use the format! syntax to write data into a buffer.

writeln!

Use the format! syntax to write data into a buffer, appending a newline.